EP1685138A1

EP1685138A1 - Regiospecific synthesis of nicotine derivatives

Info

Publication number: EP1685138A1
Application number: EP03790030A
Authority: EP
Inventors: Daniel L. Comins; Laura S. King; Emilie Despagnet
Original assignee: North Carolina State University
Current assignee: North Carolina State University
Priority date: 2003-11-17
Filing date: 2003-11-17
Publication date: 2006-08-02
Anticipated expiration: 2023-11-17
Also published as: AU2003293039B2; AU2003293039C1; EP1685138A4; AU2003293039A1; EP1685138B1; DE60329721D1; ATE445611T1; WO2005058920A1; CA2546260A1; JP2007521245A

Abstract

Methods of synthesizing nicotine analogs and derivatives are described. The methods are particularly useful for the regioselective production of enantiomerically pure nicotine analogs having substituents at the C4 position. Intermediates useful for the synthesis of such compounds are also described.

Description

REGIOSPECIFIC SYNTHESIS OF NICOTINE DERIVATIVES Laura S. King, Emilie Despagnet and Daniel L. Comins

Related Applications This application claims the benefit of Daniel L. Comins and Laura S. King, Regioselective Synthesis of C-4 Substituted 1 ,4-Dihydronicotines, United States Provisional

Patent Application Serial No. , filed November 22, 2002, Internal Number 02-67, the disclosure of which applicants specifically intend be incorporated by reference herein in its entirety.

Field of the Invention The present invention concerns methods and intermediates useful for the regiospecific synthesis of compounds active for modulating nicotinic acetylcholine receptors.

Background of the Invention Acetylcholine receptors are involved in the modulation of of a variety of physiological and behavioral functions, including neuroendocrine function, respiration, mood, motor control and function, focus and attention, concentration, memory and cognition, and substance abuse. Ligands for acetylcholine receptors have been demonstrated to have effects on attention, cognition, appetite, substance abuse, memory, extrapyramidal function, cardiovascular function, pain and gastrointestinal motility and function. The distribution of acetylcholine receptors that bind nicotine, i.e., nicotinic acetylcholine receptors, is widespread in the brain. In the periphery, acetylcholine receptors are found in muscle, autonomic ganglia, the gastrointestinal tract and the cardiovascular system (see, e.g., US Patent No. 5,594,011). Acetylcholine receptors have been shown to be decreased, among other things, in the brains of patients suffering from Alzheimer's disease, and Parkinson's disease, as well as diseases associated with dementia, moior dysfunction and cognitive impairment. Such correlations between acetylcholine receptors and nervous system disorders suggest that compounds that modulate acetylcholine receptors will have beneficial therapeutic effects for many human nervous system disorders. U.S. Patent No. 5,594,01 1 to McDonald et al.. assigned to SIB1A Neuroscience, describes compounds such as S1B-1508Y that modulate nicotinic acetylcholine receptors. Such compounds are useful for, among other things, the treatment of Parkinson's disease. See also U.S. Patent No. 5,723,477 to McDonald et al. Unfortunately, nicotine analogs are difficult compounds to synthesize, and there is a continuing need for new methods of making the same, as well as intermediates useful for the synthesis of nicotine analogs.

Summary of the Invention In general, the present invention provides regiospecific methods for the production of enantiomerically pure nicotine analogs bearing substituents other than hydrogen at the C4 position. Accordingly, a first aspect of the present invention is a regiospecific method of making a compound of Formula I:

wherein. R⁴ is alkyl, alkenyl, alkynyl, aryl or SiR²⁰R²¹R²², wherein R²⁰, R²¹ and R²² are each independently selected from the group consisting of alkyl, alkenyl, alkynyl and aryl; R¹ is alkyl, aryl, alkenyl, alkynyl, alkoxy, -NR"₂ or -SR", where R" is alkyl, aryl, alkenyl, alkynyl, or alkoxy; R², R\ and R⁶ are each independently selected from the group consisting of H, alkyl, aryl, alkenyl, alkynyl, alkoxy, and halo; R⁷ is selected from the group consisting of consisting of H and alkyl; A is a 1 , 2 or 3 atom bridging species which forms part of a saturated or monounsaturated 5-, 6- or 7-membered ring including N⁷, C⁸, C^'' and B; B is selected from -0-, -S-, -NR¹"-, wherein R¹⁰ is selected from hydrogen, alkyl, aryl, substituted aryl, alkylaryl, substituted alkylaryl, arylalkyl, substituted arylalkyl; -C¹⁰HR^{I Oa}-, wherein R^{I Oa} is selected from hydrogen, alkyl, hydroxyalkyl. aryl. aryloxyalkyl, fluoro, tπ luoromethyl, cyano, cyanomethyl, --OR', -NR'₂, or -SR', wherein each R' is independently hydrogen, alkyl, alkenyl, alkynyl or aryl, provided, however, that neither the -NR'₂ nor the - SR' functionality is conjugated with an alkenyl or alkynyl functionality; or B is =C¹⁰R^10a or =N-, preferably provided there is no double bond in the ring between A and B, or between B and C⁹ when there is a double bond between N⁷ and C⁸, and preferably provided that B is not a heteroatom when A is a 1 atom bridging species; and R⁹ and R^9a are each independently selected from hydrogen, alkyl, hydroxyalkyl, aryl, aryloxyalkyl, fiuoro, trifluoromethyl, cyano, cyanomethyl, -OR', -NR'₂, or -SR', wherein each R' is as defined above, preferably provided, however, that neither the -NR'₂ nor the -SR' functionality is conjugated with an alkenyl or alkynyl functionality; comprising: reacting an organometallic nucleophile R Met, where R is as given above and Met is a metal, with a compound of the formula:

wherein A, B. R², R⁵, R⁶, R⁷, R⁹, and R^9a are as given above, and a compound of the formula R'COX , wherein R is as given above and X¹ is halo, to produce a compound of Formula I. A second aspect of the present invention is a compound of Formula I:

wherein: A, B, R¹, R², R⁴, R⁵, R⁶, R⁷. R°, and R^9a are as described above. Optionally but preferably the compound is enantiomerically pure. A further aspect of the present invention is a method of making a compound of Formula II.

wherein A, B, R², R⁴ R⁵, R⁶, R⁷ R⁹, and R^9a are as described above; comprising oxidizing a compound of Formula I:

wherem A, B, R¹, R², R⁴, R\ R⁶, R , R⁹, and R ^a are as given above to produce a compound of Formula II. A further aspect of the present invention is an enantiomerically pure C4-substituted nicotine analog produced by the method described above (i.e.. a compound of Formula II). An example of a particular embodiment is an enantiomerically pure compound of Formula II

wherein R⁴ is as described above; and A, B, R². R^, R⁶, R R⁹, and R^9a are as described above, subject to the proviso that R is different from at least one of (and in some embodiments all of) R , R⁵ and R⁶. Another embodiment is an enantiomerically pure compound of Formula II:

wherein R⁴ is SiR ,2^zQ^u _rR₎21_r R₎ 22 , wherein R > 2^Δ0 , R .21' and R 2"2 are as given above; and A, B, R^z, R\ R⁶, R⁷,R⁹, and R ^a are as descnbed above. A further aspect of the present invention is a method of making a compound of Formula III:

wherein: A, B, R², R⁵, R⁶, R⁷ R⁹, and R^9a are as descnbed above; comprising oxidizing a compound of Formula II:

wherein A, B, R, R², R²², wherein R² , R²¹ and R ^" are each independently selected from the group consisting of alkyl alkenyl, alkynyl and aryl in a polar protic solvent to produce a compound of Formula III. A still further aspect of the present invention is an enantiomerically pure compound of Formula III as described above.

The foregoing and other objects and aspects of the present invention are explained in greater detail below.

Detailed Description of the Preferred Embodiments "Alkyl" as used herein refers to straight or branched chain alkyl groups having in the range of about 1 up to 12, 20, or 30 carbon atoms. In some embodiments the alkyl can be a lower alkyl. "Lower alkyl" refers to straight or branched chain alkyl radicals having in the range of about 1 up to 6 carbon atoms. Alkyl and lower alkyl may be substituted or unsubstituted unless specified otherwise herein; "substituted alkyl" refers to alkyl, cycloalkyl or lower alkyl groups further bearing one or more substituents such as hydroxy, alkoxy (of a lower alkyl group), aryl, mercapto (of a lower alkyl group), halogen, trifluoromethyl, cyano, nitro, amino, carboxyl, carbamate, sulfonyl, silyl, sulfonamide, and the like. Representative examples of alkyl include, but are not limited to, methyl, ethyl, n-propyl, iso-propyl, n-butyl, sec -butyl, iso-butyl, tert-butyl, n-pentyl, isopentyl, neopentyl, n-hexyl, 3-methylhexyl, 2,2- di ethylpentyl, 2,3-dimethylpentyl, n-heptyl, n-octyl, n-nonyl, n-decyl, cyclohexyl, and the like. "Alkoxy" as used herein refers to a compound of the formula RO-, where R is alkyl or lower alkyl (which may be substituted or unsubstitued unless specified otherwise) as given above. "Alkenyl" refers to straight or branched chain hydrocarbyl groups such as alkyl or lower alky! groups as described above (and which may be substituted or unsubstituted unless specified otherwise) and having at least one carbon-carbon double bond. "Alkynyl" refers to straight or branched chain hydrocarbyl groups such as alkyl or lower alkyl groups as descnbed above (and which may be substituted or unsubstituted unless specified otherwise) and having at least one carbon-carbon triple bond "Aryl," as used herein, refers to a monocychc carbocychc or heterocyclic nng system or a bicychc carbocychc or heterocyclic fused nng system having one or more aromatic nngs Examples ol aryl include but are not limited to azulenyl, indanyl, mdenyl, naphthyl, phenyl, tetrahydronaphthyl, and the like The aryl groups may be substituted or unsubstituted unless specified otherwise and when substituted can for example be substituted with 1, 2, 3, 4, or 5 substituents independently selected from alkyl, alkenyl, alkenyloxy, alkoxy, alkoxyalkoxy, alkoxycarbonyl, alkylcarbonyl, alkylcarbonyloxy, alkylsulfinyl, alkylsulfonyl, alkylthio, alkynyl, aryl, aryloxy, azido, arylalkoxy arylalkyl, aryloxy, carboxy, cyano, formyl, halogen, haloalkyl, haloalkoxy, hydroxy, hydroxyalkyl, mercapto, nitro, sulfamyl, sulfo, sulfonate, -NR'R" (wherem R' and R" are independently selected from hydrogen, alkyl, alkylcarbonyl, aryl, arylalkyl and formyl), and -C(O)NR'R" (wherem R' and R" are independently selected from hydrogen, alkyl, alkylcarbonyl, aryl, arylalkyl, and formyl) "Organometalhc nucleophile" are generally expressed as R Met, where Met is a suitable metal such as magnesium, manganese, lithium, sodium, copper, cenum, zmc, cadmium, aluminum or titanium Additional groups R may optionally be present and a halide may optionally be present as is known in the art Suitable organometalhc nucleophiles include Gngnard rtagents "Gngnard reagent" as used herein refers to an organomagnesium hahdes, R⁴MgX, having a carbon-magnesium or silicon-magnesium bond (or their equihbnum mixtures in solution with R⁴ ₂Mg + MgX₂), where R is a hydrocarbyl or silyl group such as alkyl, alkenyl, alkynyl or aryl, or a corresponding silyl gioup "Halo" refei s to fiuoro, chloro, bromo or lodo The disclosures of all United States patent teferences cited herein are to be incorporated herein by reference in their entirety Starting materials for the reactions described herein include both nicotine and nicotine analogs and derivatives, including analogs substituted at the 2, 5 and 6 position, including but not limited to those descnbed in US Patents Nos 5,594,01 1 and 5,723,477 (including both novel compounds described therein and known compounds described therein) Examples of such starting tnatei lals are are illustrated by Formulas i-ii below

wherein: R², R⁵, and R⁶ are each independently selected from the group consisting of H, alkyl, aryl, alkenyl, alkynyl, alkoxy, and halo, preferably H or alkyl (e.g. methyl); R⁷ is selected from the group consisting of H and alkyl (e.g., methyl); A is a 1 , 2 or 3 atom bridging species which forms part of a saturated or monounsaturated 5-, 6- or 7-membered ring including N , C , C and B; B is selected from -O-, -S-, -NR¹⁰-, wherein R¹⁰ is selected from hydrogen, alkyl, aryl, substituted aryl, alkylaryl, substituted alkylaryl, arylalkyl, substituted arylalkyl; -C^loHR^10a-, wherein R^10a is selected from hydrogen, alkyl, hydroxyalkyl, aryl, aryloxyalkyl, fiuoro, trifluoromethyl, cyano, cyanomethyl, -OR', -NR'₂, or -SR', wherein each R' is independently hydrogen, alkyl, alkenyl, alkynyl or aryl, preferably provided, however, that neither the -NR'₂ nor the -SR' functionality is conjugated with an alkenyl or alkynyl functionality; or B is =C¹⁰R¹⁰- _or _^ p_ref_eraDiy provided there is no double bond in the ring between A and B, or between B and C when there is a double bond between N⁷ and C⁸, and preferably provided that B is not a heteroatom when A is a 1 atom bridging species; and R and R ^> are each independently selected from hydrogen, alkyl, hydroxyalkyl, aryl, aryloxyalkyl, fiuoro, trifluoromethyl, cyano, cyanomethyl, -OR', -NR'₂, or -SR', wherein each R' is as defined above, preferably provided, however, that neither the —NR'₂ nor the -SR' functionality is conjugated with an alkenyl or alkynyl functionality. As noted above, a first aspect of the present invention is a regiospecific method of making a compound of Formula I: wherem. R⁴ is alkyl, alkenyl, alkynyl, aryl or SιR²⁰R^2lR²², wherein R²⁰, R²¹ and R²² are each independently selected from the group consisting of alkyl, alkenyl, alkynyl and aryl, R¹ is alkyl, aryl, alkenyl, alkynyl, alkoxy, -NR"₂ or -SR", where R" is alkyl, aryl, alkenyl, alkynyl, or alkoxy, R², R⁵, and R⁶ are each independently selected from the group consisting of H, alkyl, aryl, alkenyl, alkynyl, alkoxy, and halo; R⁷ is selected from the group consisting of consisting of H and alkyl, A is a 1 , 2 or 3 atom bndgmg species which forms part of a saturated or monounsaturated 5-, 6- or 7-membered nng including N , C , C and B, B is selected from -O-, -S-, -NR¹ -, wherem R¹⁰ is selected from hydrogen, alkyl, aryl, substituted aryl, alkylaryl, substituted alkylaryl, arylalkyl, substituted arylalkyl, -C^lϋHR^10a-, wherem R^{I O} is selected from hydrogen, alkyl, hydroxyalkyl, aryl, aryloxyalkyl, fiuoro, trifluoromethyl, cyano, cyanomethyl, —OR', -NR'₂, or — SR', wherein each R' is independently hydrogen, alkyl, alkenyl, alkynyl or aryl, provided, however, that neither the -NRS nor the - S functionality is conjugated with an alkenyl or alkynyl functionality, or B is =C^{l o}R^IOa or =N-, preferably provided there is no double bond in the ring between A and B, or between B and C⁹ when there is a double bond between N⁷ and C⁸, and preferably provided that B is not a heteroatom when A is a 1 atom bndging species; and R and R^<)a are each independently selected from hydrogen, alkyl, hydroxyalkyl, aryl, aryloxyalkyl, fiuoro, tπfluoromethyl, cyano, cyanomethyl, -OR', -NR'₂, or -SR', wheiein each R' is as defined above, preferably provided, however, that neither the -NR'₂ nor the -SR' functionality is conjugated with an alkenyl or alkynyl functionality The method compnses reacting an organometalhc nucleophile R⁴Met, where R⁴ is as given above and Met is a metal, with a nicotine or nicotine analog starting material such as a compound of the formula (i) or (ii) as given above, and a compound of the formula R'COX¹ , wherein R is as en above and X is halo, to produce a compound of Formula 1. In some embodiments the organometalhc nucleophile is a Grignard reagent. Grignard reagents suitable for carrying out the present invention can be prepared in accordance with known techniques, including but not limited to those described in US Patents Nos. 6,617,282; 6,608,212; 6,603,000; 6,600,040; 6,593,471 ; 6,590,125; 6,590,125; 6,590,103; 6,579,993; 6,570,107; 6,569.799; etc. In general, Grignard reagents may be prepared from magnesium which may be in the form of magnesium granules, magnesium turnings, magnesium dust, magnesium powder, suspension of magnesium in oil, and the like. To minimize safety risks, the use of magnesium granules is preferred. Preferred solvents for preparing the Grignard reagent comprise an organic solvent such as toluene, tetrahydrofuran (THF), diethyl ether, diglyme, methyl t-butyl ether, and mixtures thereof. The time and temperature of the reaction is not critical, but in general the reaction may be carried out from 1 -24 hours at a low temperature (e.g . between -100 and 0 °C) in a suitable solvent such as tetrahydrofuran, toluene, or an ether solvent, until the reaction is quenched by addition of a suitable quenching agent such as water or aqueous ammonium chlonde. Compounds of Formula I produced by such methods are optionally but preferably enantiomerically pure, and may optionally but in some embodiments preferably bear a group R that is different from at least one, or all of, groups R², R^l and R⁷. In some embodiments, R⁴ is alkyl, alkenyl, alkynyl, or aryl. In some embodiments. R⁴ is SiR²⁰R²¹R²², and wherein R²⁰, R²' and R²² are each independently selected from the group consisting of alkyl alkenyl, alkynyl and aryl. In some embodiments, R^l is alkyl A further aspect of the present invention, as also noted above, is a method of making a compound of Formula II:

wher in A, B, R^", R R^J, R , R⁷, R¹', and R^9a are as described above. The method compπses o \idι/,ιng a compound of Formula 1 as described above in an organic solvent such as toluene to produce a compound of Formula II. The oxidi/ing step may be carried out with an suitable oxidizing agent, including but not limited to air. sulfur, nitric acid, KMnO , cenc ammonium nitrate, chloraml and 2,3-dιchloro-5,6-dιcyano- l ,4-benzoqumone. The time and temperature of the oxidizing step is not cntical and will usually depend upon the particular oxidizing agent used, but may be from one hour to two to four days, and a temperature between room temperature and 150 °C (e g , by refluxing in toluene) The method may be utilized to produce enantiomencally pure C4-substιtuted nicotine analogs, e.g , compounds of Formula II, particularly compounds in which R⁴ is different from at least one, two, or all three of R , R and R^ό One embodiment is enantiomencally pure compounds subject to the proviso that R⁴ is different from at least one, two, or all three of of R², R⁵ and R⁶, another embodiment is enantiomencally pure compounds of Formula II wherein R⁴ is SιR²⁰R^{2 l} R²², wherem R²⁰, R²¹ and R²² are each independently selected from the group consisting of alkyl, alkenyl, alkynyl and aryl, wherein A, B, R², R⁵, R⁶, R⁷ R⁹, and R^9a are as described above The invention further provides a method of making a compound of Formula III

wherei n A, B, R², R⁵, R⁶, R⁷, R⁹, and R^9a are as descnbed above, the method comprises oxidizing a compound of Formula II as described above, where R⁴ is SιR^2ϋR²¹R²², to produce a compound of Formula III. The oxidizing step is prefrerably carried out m a polar prolic solvent to produce a compound of Formula III. Example solvents include but are not limited to methanol, ethanol, propanol, and butanol, including mixtures thereof The oxidizing step is preferably carried out with a peroxide oxidizing agent such as hydrogen peroxide in the presence of fluoride, which may be provided by any suitable fluoride souice such as KHF₂. The time and temperature of the reaction is not critical, but in genei al may be from 1-24 hours, and may conveniently be carried out at a temperature between loom temperature and 100 °C hnantiomeπcally pure compounds of Formula III which can be produced by such processes aie also an aspect of the invention, as noted above Utility. Compounds of the present invention are useful the manners descnbed in US Patents Nos 5,594,01 1 to McDonald et al and 5,723,477 to McDonald et al In summary, methods and intermediates of the present invention are useful for producing pharmacologically and pharmaceutically active compounds, including compounds useful for the treatment of neurological disorders such as Parkinson's disease, Alzheimer's disease, motor dynsfunction and cognitive impairment in human and animal subjects (particularly mammalian subjects such as dogs, cats, and non-human pnmates), as well as compounds for use as an alternative to nicotine as an aid to smoking cessation programs, as insecticides, etc Dosage of the compound may be determined in accordance with standard techniques, but in some embodiments will be from 0 001 or 0 05 mg/kg/day, up to about 10 or 100 mg/kg/day The compounds disclosed herein can be prepared in the form of their pharmaceutically acceptable salts Pharmaceutically acceptable salts are salts that retain the desired biological activity of the parent compound and do not impart undesired toxicological effects Examples of such salts aie acid addition salts formed with inorganic acids, for example hydrochlonc acid, hydrobiomic acid, sulfuπc acid, phosphoric acid, nitnc acid and the like, and salts formed with organic acids such as, for example, acetic acid, oxalic acid, tartan c acid, succinic acid, maleic acid, fumanc acid, gluco c acid, citric acid, malic acid, ascoibic acid, benzotc acid tannic acid, palmitic acid, alginic acid, polyglutamic acid, naphthalenesulfonic acid methanesulfonic acid, p-toluenesulfonic acid, naphthalenedisulfomc acid, polygalacturonic acid, and the like The compounds described above may be formulated for administration in a pharmaceutical earner in accordance with known techniques See e g , Remington, The Science And Practice of Pharmacy (9^l Ed 1995) In the manufacture of a pharmaceutical formulation according to the invention, the active compound (including the physiologically acceptable salts thereof) is typically admixed with, inter alia, an acceptable carrier The carrier must, of course, be acceptable in the sense of being compatible with any other ingredients in the formulation and must not be deletenous to the patient The earner may be a solid or a liquid, or both, and is preferably formulated with the compound as a unit-dose foπnulation, for example a tablet, which may contain from 0 01 oi 0 5% to 95% or 99% by weight of the active compound One or more active compounds may be incorporated in the formulations of the invention which may be prepared by any of the well known techniques of phannacy consisting essentially of admixing the components optionally including one or more accessory ingredients The formulations of the invention include those suitable for oral, rectal, topical, buccal (e g , sub-lingual), vaginal, parenteral (e g , subcutaneous, intramuscular, mtradermal, or intravenous), topical (i e both skin and mucosal surfaces, including airway surfaces) and transdermal administration, although the most suitable route in any given case will depend on the nature and seventy of the condition being treated and on the nature of the particular active compound which is being used Formulations suitable for oral administration may be presented in discrete units, such as capsules, cachets, lozenges, or tablets, each containing a predetermined amount of the active compound, as a powder or granules, as a soluuon or a suspension in an aqueous or non-aqueous liquid, or as an oil-in-water or water- -oil emulsion Such formulations may be prepared by any suitable method of pharmacy which includes the step of bnngmg into association the active compound and a suitable earner (which may contain one or more accessory ingredients as noted above) In general, the formulations of the invention are prepared by uniformly and intimately admixmg the active compound with a hquid or finely divided solid earner, or both, and then, if necessary, shaping the resulting mixture For example, a tablet may be prepared by compressing 01 molding a powder or granules containing the active compound, optionally with one or more accessory ingredients Compressed tablets may be prepared by compressing, in a suitable machine, the compound m a free-flowing form, such as a powder or granules optionally mixed with a binder, lubncant, inert diluent, and/or surface active/dispersing agent(s) Molded tablets may be made by molding, in a suitable machine, the powdered compound moistened with an inert liquid binder Formulations suitable for buccal (sub-hngual) administration include lozenges compnsmg the active compound in a flavoured base, usually sucrose and acacia or tragacanth, and pastilles compnsmg the compound in an inert base such as gelatin and glycerin or sucrose and acacia Formulations of the present invention suitable for paienteral administration compπse stenle aqueous and non-aqueous injection solutions of the active compound, which preparations are prefei ably isotonic with the blood of the intended recipient These preparations may contain anti-oxidants, buffers, bactenostjts and solutes which rendei the foiτnulation isotonic with the blood of the intended recipient Aqueous and non-aqueous sterile suspensions may include suspending agents and thickening agents The formulations may be pi esented in umt\dose 01 multi-dose containers, for example sealed ampoules and vials, and may be stored in a freeze-dπed (lyophihzed) condition requiring only the addition of the sterile liquid earner, for example, saline or watei-for-mjection immediately prior to use Extemporaneous injection solutions and suspensions may be prepared from stenle powders, granules and tablets of the kind previously descnbed For example, m one aspect of the present invention, there is piovided an mjectable, stable, stenle composition compnsmg a compound of the invention, or a salt thereof, m a unit dosage form in a sealed container The compound or salt is provided in the form of a lyophihzate which is capable of being l econstituted with a suitable pharmaceutically acceptable earner to form a liquid composition suitable for injection thereof into a subject When the compound or salt is substantially water-insoluble, a sufficient amount of emulsifying agent which is physiologically acceptable may be employed in sufficient quantity to emulsify the compound or salt m an aqueous earner One such useful emulsifying agent is phosphatidyl chohne Formulations suitable for rectal administration are preferably presented as unit dose suppositones These may be prepared by admixmg the active compound with one or more conventional solid earners, for example, cocoa butter, and then shaping the resulting mixture Formulations suitable for topical application to the skin preferably take the form of an ointment, cream, lotion, paste, gel, spray, aerosol, or oil Carriers which may be used include petroleum jelly, lanohne, polyethylene glycols, alcohols, transdermal enhancers, and combinations of two or more thereof Formulations suitable for transdermal admmistiation may be presented as discrete patches adapted to remain in intimate contact with the epidermis of the recipient for a prolonged period of time Formulations suitable for transdermal administration may also be delivered by iontophoresis {see, for example, Pharmaceutical Research 3 (6) 318 (1986)) and typically take the form of an optionally buffered aqueous solution of the active compound Suitable formulations comprise citrate or bιs\tns buffer (pH 6) or ethanol/water and in some embodiments contain from 0 1 to 0 2M active ingredient The present invention is explained in greater detail in the following non-limiting Examples

EXAMPLE 1 Preparation of l-[4-(Dimethylphenyisιlany!) -3-(l-methylpyrrolιdin-2-yl)-4 -pyridin-l-yl|-2,2-dimethylpropan-l-one (I) 2) PhMe₂SiMgCI, CuBr la lb

First a solution of (dimethylphenylsilyl)magnesium bromide (4 mmol) in THF was prepared according to our previous procedure and cooled to -78 °C. A solution of CuBr«SMe₂ (0.4 g, 2 mmol) in 4 mL of diisopropyl sulfide was added dropwise to the solution of the Grignard reagent prepared above. The resulting solution was then stirred at - 78° C for 30 min during which time it turned brown-orange. In the meantime, a solution of nicotine (0.16 mL, 1 mmol) in 1 mL of THF was cooled to 0 °C and was treated with pivaloyl chloride (0.12 mL, 1 mmol). The salt was stirred at 0 °C for 1 .5 h. It was then cooled to -78 °C and the solution of cuprate prepared above was injected via a double tipped needle surrounded by dry ice. The reaction mixture was then stirred at -78 °C for 4 h and then at - 30 °C overnight. After warming to room temperature, the mixture was quenched with a saturated aqueous solution of NH₄C1. The aqueous phase was extracted 3 times with ether. The combined organic layers were washed 3 times with 20% NH₄Cl NH₄OH (50:50), 1 time with water, one time with brine and then dried over K₂COv The solvent was removed under reduced pressure to afford 0.6 g of crude material. Purification by radial PLC (5% EtOAc hexanes) yielded 0.312 g (81%) of product I as a mixture of diastereomers and 0.04 g (25 %)of nicotine. The diastereomers were separated by RPLC (hexanes) and the de was determined to be 68%. Diastereomer la: IR (neat) 2960, 1649, 1321 , 1 1 15, 814 cm^"' ; Η NMR(400 MHz, CDC1₃) δ 7.49-7.29 (m, 6 H), 6.97 (s, 1 H), 4.99 (dd, 1 H, J = 5.6 and 7.2 Hz), 2.99 (t, 1 H, J = 7.2 Hz), 2.36 (d, 1 H. J = 5.6 Hz), 2.31 (t, 1 H, J= 8 Hz). 2.15 (s, 3 H), 2.06-1.00 (m, 14 H), 0.35-0.29 (m, 6 H); '^' C NM R ( 100 MHz, CDCl₃) δ 172.4. 148.7, 146.4, 133.1, 133.5, 129.1 , 128.9, 127.6, 127.4, 123.7, 1 18.6, 110.2, 68.1 , 66.8, 56.6, 40.8, 38.7, 35.4, 32.1. 30. 1 , 27.6, - 1.5, -1.6. HRMS Calcd for C₂₃H₃₄N₂OSi: 383.25 19 [ M + H]⁺. Found: 383.2520 [M+H]⁺. [α] * -67.3 (c 4, CH₂C1₂). Diastereomer lb: IR (neat) 2960, 1849, 1321 cm^'1 ; Η NMR (400 MHz, CDCI₃) δ 7.51-7.29 (m, 6 H), 6.86 (s, 1 H), 4.97 (t, 1 H, J= 6.6 Hz), 3.75-3.1 (m, 2 H), 2.88 (t, 1 H, J = 6.4 Hz), 2.45-1.57 (m, 8 H), 1.27 (s, 9 H), 0.35 (s, 3 H), 0.31 (s, 3 H); ^l C NMR (100 MHz, CDC ) δ 172.6, 149.0, 146.7, 137.7, 133.9, 133.8, 128.8, 127.8, 127.6, 127.4, 111.5, 69.5, 56.5, 56.1, 40.3, 39.8, 39.0, 27.7, 27.5, 22.9, 22.4, -1.3, -1.4; HRMS Calcd for C₂₃H₃₄N₂OSι: 383.2519 [M+H]⁺. Found: 383.2520 [M+H]⁺. [α] ² _D ⁱ +23.8 (c 7, CH₂C1₂).

EXAMPLE 2 Preparation of 4-(Dimethylphenylsilanyl)-3-(l-methylpyrrolidin-2-yl)pyridine (II)

Sβ, toluene la

To a solution of 1 ( 1 g, 2.6 mmol) in 80 mL of toluene was added sublimed sulfur (0.09 g, 2.6 mmol). The reaction mixture was stirred and heated at 90 °C for 2 days. Evaporation of the solvent under reduced pressure afforded 1.11 g of crude product. Purification by radial PLC (5% EtOAc/hexanes) yielded 0.6 g (76 %) of product II as a yellow oil. fR (neat) 2950, 2774, 1579, 1427, 1251 cm^"1; ^lH NMR (400 MHz, CDCI₃) δ 8.72 (s, 1 H), 8.27 (d, 1 H, J = 6.8 Hz), 7.31 -7.13 (m, 6 H), 3.03 (t, 1 H, J = 10.8 Hz), 2.95-2.90 (m, 1 H), 1.97-1.86 (m, 2 H), 1.69 (s, 3 H); ^l3C NMR (100 MHz, CDC1₃) δ 148.6, 146.2, 145.4, 144.3, 137.0, 133.5, 132.6, 12SΛ⁾, 128.0, 127.5, 127.1, 68.0, 56.0, 39.4, 35.3, 22.1, -1.69, -1.74. HRMS Calcd for C₁₈H₂₄N:Si: 297.1787 [M+H]⁺. Found: 297.1801 [M+H]⁺. [α] -82.05 (c 4, CH₂C1₂).

EXAMPLE 3 Preparation of 3-(l-Methylpyrrolidin-2-yl)pyridin-4-ol (III) ¹¹ III

To a solution of II (0.9 g, 3.2 mmol) in 10 L of methanol was added potassium hydrogen fluoπde (0.25 g, 3.2 mmol). A solution of 30% hydrogen peroxide in water (0.88 L, 7.7 mmol) was slowly added, and the reaction mixture was stirred and heated at 55 °C for 8 h. To the crude mixture was added K CO₃ until the pH of the solution became slightly basic (pH 8-9). After filtration of the solid and evaporation of the solvent, the crude product was purified by radial PLC (EtOAc) to yield 82% of III as a white solid! IR (neat) 2598, 23448, 1643 cm^"1 ; Η NMR (300 MHz, CDC1₃) δ 8.68 (s, 1 H), 8.58-8.56 (m, I H), 8.12 (dd, 1 H, J = 1.5 and 8 Hz), 7.47 (dd, 1 H, J - 5.1 ans 8 Hz), 4.61 (dd, 1 H, J = 7 2 and 12 Hz), 3.79-3.59 (m, 2 H), 2.94 (s, 3 H), 2.72-2.1 (m, 4 H); ^{l 3}C NMR (75 MHz, CD OD) δ 170.5, 152.8, 151.4, 141.3, 124.9, 78.3, 71.4, 54.1, 29.5, 21.1. HRMS Calcd for C,₀H_I4N₂O: 179.1 184. Found: 179.1190 [M+H] +. [α] " : +23.8 (c = 0.8, MeOH). IR (neat) 2598, 23448, 1643 cm^"1 ; Η NMR (300 MHz,) δ 8.68 (s, I H), 8.58-8.56 (m, 1 H), 8 12 (dd, 1 H, J = 1.5 and 8 Hz), 7.47 (dd, 1 H, J = 5.1 ans 8 Hz), 4.61 (dd, 1 H, J = 7.2 and 12 Hz), 3.79-3.59 (m, 2 H), 2.94 (s, 3 H), 2.72-2.1 (m, 4 H); ^, C NMR (75 MHz, CD3OD) δ 1 70.5, 152.8, 151.4, 141.3, 124.9, 78.3, 71.4, 54.1, 29.5, 21.1. HRMS Calcd for C|₀H|₄N O: 179.1184. Found: 179.1 190 [M+HJ+. [α] +23.8 (c 8, MeOH).

EXAMPLE 4 3-((2S)-l-Methylpyrrolidin-2-yl)-4-phenylpyridiπe l-[(4S)-3-((2S)-l-Methylpyrrolιdm-2-yl)-4-phenyl((l ,4-dιhydropyπdyl)]-2,2- dιmethylpropan-1 -one (49 1 mg, 0 15 mmol) was dissolved m 2 mL of toluene Sulfur (5 mg, 1 0 mmol) was added and the solution was refluxed for 32 h. The solution was evaporated to dryness and the residue punfied by radial PLC (silica gel, 1% TEA/EtOAc) to give 21 4 mg (59%) of a white solid mp 87-89 °C, IR (CHClj) 702, 843, 1042, 1004, 1473, 1587, 2779, 2966 cm^"1, Η NMR (CDC1₃, 400 MHz) δ 1 80 to 1 72 (m, 2H), 2.00 to 1 88 (m, 1 H), 2 08 to 2.05 (m, 1H), 2 10 (s, 3H), 2 16 to 2 12 (m, 2H), 3 17 (t, 1H, J= 7 6 Hz), 7 08 (d, 1H, J = 5 2 Hz), 7 26 to 7 24 (m, 2H). 7 44 to 7 43 ( , 3H). 8 49 (d, 1H, J= 5 2 Hz), 8 92 (s, 1 H). ^I C NMR (CDC1₃, 100 MHz) 0 23 0, 35 8, 40 6, 57 0, 65 4, 124.0, 128.1, 128 5, 128 9, 139 0, 147 5, 149 8, 150 2 HRMS Calcd for Cι₆H₁₈N₂ 239 1548 Found: 239 1561 [α] - 131 5 (c l. EtOH)

EXAMPLE 5 l-[(4S)-3-((2S)-l-Methy!pyrrolidin-2-yl)-4- phenyl((l,4-dihydropyridyl)]-2,2-dimethylpropan-l-one

Pivaloyl chloride (0 123 mL. 1 0 mmol) was added dropwise to a solution of nicotine (0 16 mL, 1 0 mmol) in 2 mL of THF at 0 °C, and the resulting solution was stirred for 1 hour to form a heterogenous mixture containing the white, solid I -acyl pyπdinium salt Concurrently, phenylmagnesium biomide (1 1 L, 1 1 mmol) was added slowly to a solution of CuBr.DMS ( 164 mg, 0 8 mmol) in 5 mL of THF at -78 °C, and the resulting yellow- orange solution was stirred for 30 mm The solution was cooled to -78 °C, and the organocopper reagent was added via a double tipped needle The resulting mixture was stirred for 3 h The reaction mixture was quenched with 2 mL of saturated NH₄C1, and the white solid that formed was lemoved by vacuum filtration. The filtrate was extracted with EtOAc (3 x 10 mL), and the combined organic extracts were washed with 10% NH₄OH (aq) until the persistent blue color vanished from the organic phase The organic layer was washed with saturated aqueous NaHCO3, dned (K₂CO₃), filtered over Celite, and concentrated vacuo The crude yellow oil was purified by radial PLC (silica gel, l%TEA/EtOAc) to give 245 mg (76%) of product as a light yellow solid mp 84-85 °C, ER (CHC1₃) 2970, 2776, 1739, 1661, 1455, 1311 , 1209, 1151, 1014, 968, 888, 761 , 700 cm^"1 , 1H NMR (CDCI₃, 400 MHz) δ 1 32 to 1 13 (m, 2H), 1 39 (s, 9H), 1 52 to 1 43 (m, 1H), 1 68 to 1 57 (m, 1H), 2 02 ( q, lH, J = 9 6 Hz) 2 10 (s, 3H), 2 36 (t, 1H, J = 8 0 Hz), 2 98 (t, 1H, J = 8 8 Hz), 3 92 (d, 1H, J = 4 0 Hz), 5 09 (dd, 1 H, J= 8 0 Hz and 4 4 Hz), 7 28 to 7 17 (m, 6H), 7 41 (s, 1H), ^πC NMR (CDCI₃, 100 MHz) δ 22 8, 28 5, 34 1, 39 761 , 40 1, 44 1 , 56 6, 70 0, 1 11 4, 120 6, 123 0, 126 9, 128 5, 128 7, 145 5, 174 2 HRMS Calcd for C₂,H₂₈N₂O 325 2280 Found 325 2286 [α] - 25 2 (c 1 , EtOH)

EXAMPLE 6 l-[3-((2S)-l-Methylpyrrolidin-2-yl)-4-methyl ((l,4-dihydropyπdyl)l-2,2-dimethylpropan-l-one Light yellow oil [α] " - 64 {c 4 5, EtOH) ER (neat), 739, 939, 1043. 1158, 1208, 1317, 1403, 1477, 1632, 1659, 2775, 2967 cm^{"1 l}U NMR (CDCI₃, 400 MHz) δ 1 11 (d, J = 6 8 Hz, 3H), 1 34 (s, 9H), 1 64 to 1 86 (m, 3H), 1 88 to 1 96 (m, 1H), 2 10 (dd, J= 17 2 Hz, 7 2 Hz, 1H), 2 21 (s, 3H), 2 49 (t, J= 8 0 Hz, 1 H), 2 89 (m, 1H), 3 09 (t, j = 8 0 Hz, 1H), 5 02 (dd, J = 8 4 Hz, 4 8 Hz, 1H), 7 04 (d / = 8 4 Hz, 1H), 7 15 (s, 1H) ¹³C NMR (CDCI₃, 75 MHz)δ 22 9, 23 6, 27 0, 28 4, 29 9, 23 2 ^9 6, 40 8, 57 1 , 70 9, 1 13 7, 121 4, 1 23 3, 124 3, 1 73 9 HRMS (calculated 263 2123, found 263 2127)

H XAMPLE 7 l-[3-((2S)-l-lVlt thyipyrrolidin-2-yl)-4-but>l ((l,4-dihydropyridyl)j-2,2-dimethylpropan-l-one Light yellow oil. IR (neat) 739, 896, 928, 997, 1041, 1112, 1156, 1209, 1313, 1403, 1462, 1660, 2774, 2957 cm^'1. 'H NMR (CDC1₃, 300 MHz) δ 0.84 to 1.87 (t, J= 5.1 Hz, 3H), 1.21 to 1.26 (m, 3H), 1.33 (s, 9H), 1.30 to 2.09 (m, 7H), 2.19 (s, 3H), 2.47 to 2.49 (m, IH), 2.86 to 2.87 (m, IH), 3.06 to 3.10 (m, IH), 5.04 (dd, J= 6.3 Hz, 3.6 Hz, IH), 7.09 (d, J= 6.0 Hz, IH), 7.18 (s, IH). ^I3C NMR (CDC1₃, 100 MHz) δ 14.3,23.0,27.4,28.4, 32.5,35.9, 39.6,40.8, 57.0, 70.8, 111.7, 122.5, 123.0, 124.4, 173.9. HRMS (calculated: 305.2593, found: 305.2601).

EXAMPLE 8 l-[(4S)-3-((2S)-l-Methylpyrrolidin-2-yl)-4-phenyl ((1 ,4-dihydropy ridyl)]-2,2-dimethylpropan-l -one Yellow solid, mp 84-85 °C. [α] -25.2 (c 1, EtOH). IR (neat) 700, 762, 888, 968, 1015, 1151, 1209,1311,1403, 1455, 1661, 1739,2776,2970 cm^'1. ' H NMR (CDC1₃, 400 MHz)δ 1.12 to 1.32 (m,2H), 1.39 (s, 9H), 1.43 to 1.52 (m, IH), 1.57 to 1.68 (m, IH), 2.02 (q, J= 9.6H; IH), 2.10 (s, 3H), 2.36 (t, J= 8.0 Hz, IH), 2.98 (t, J= 8.8Hz, IH), 3.92 (d, J =

4.0 Hz, IH), 5.09(dd,J=8.0Hz, 4.4 Hz, IH), 7.17 to 7.28(m, 6H), 7.41 (s. IH).¹³C NMR δ 22.8, 285, 34.1, 39.8, 40.7, 44 I, 56.6, 70.0, 111.4, 120.6, 123.0, 126.9, 128.5,128.7, 145.5 , 174.2. HRMS (calculated: 325.2280. found: 325.2286).

EXAMPLE 9 l-[3-((2S)-l-MethylpyrroIidin-2-yl)-4-benzyl ((l,4-dihydropyridyl)j-2,2-dimethyIpropan-l-one Light yellow oil. IR (neat) 701,742,900,977, 1023, 1153, 1212, 1306, 1400, 1453, 1494, 1629, 1658,2774,2950 cm^"1. 'H NMR (CDC1₃, 300 MHz) δ 1.33 (s,9H), 1.75 to 2.01 ( , 4H), 2.13 to 2.17 (m, IH).2.3 (s.3H), 2.37 (dd, J= 12.4 Hz, 2Hz, IH), 2.64 (t, J= 7.6 Hz, 1H),3.11 (m, 2H), 3.27(dd,J= 12.4Hz,8.8 Hz, IH), 4.84 (dd, J= 8.4 Hz, 3.2 Hz, IH),

7.01 (d,J=8.0Hz, IH), 7.15 to 729 (m, 6H). ¹ C NMR (CDCI₃.75 MHz) δ23.4, 267,28.4, 31.9, 373,39.7, 40.9,43.7, 571,71.0, 111.0, 122.7, 124.2, 126.1, 128.4, 1 29.6, 139.8, 174.1. HRMS (calculated: 339.2436. found: 339.2447). EXAMPLE 10 3-((2S)-l-Methylpyrrolidin-2-yl)-4-butylpyridine Clear oil. [α] ³ -109.8 (c 2, EtOH). IR(neat) 837, 902, 1044, 1210, 1407, 1458, 1593, 2778, 2871 , 2957 cm^"1. Η NMR (CDC1₃, 400 MHz) δ 0.94 (t, 3H, J = 7.2 Hz), 1.34 to 1.42 (m, 2H), 1.51 to 1.55 (m, 2H), 1.61 to 1.69 (m, IH), 1.78 to 1.82 (m, IH), 1.95 to 1.97 (m, I H), 2.17 (s, 3H), 2.19 to 2.30 (m, 2H), 2.63 (t, 2H, J= 8.0 Hz), 3.25 (dt, IH, J= 8.4 Hz and 1.6 Hz), 3.32 (t, lH, J= 8.4 Hz), 7.01 (d, IH, J= 5.2 Hz), 8.34 (d. I H, J = 5.2 Hz), 8.71 (s, I H). ¹³C NMR (CDC1₃, 100 MHz) δ 14.1, 22.9, 31.7, 33.0, 34.9, 40.8, 57.5, 65.5, 123.8, 136.8, 147.8, 149.4, 149.7. HRMS (calculated: 219.1861 , found: 219.1855).

EXAMPLE 11 3-((2S)-l-Methylpyrrolidin-2-yl)-4-benzylpyridine Clear oil. [α] -113.9 (c 2, EtOH). IR (neat) 703, 762, 1045, 1253, 1456, 1590, 1 718, 2355, 2846, 2932 cm^"1. Η NMR (CDCI₃ 400 MHz) δ 1.54 to 1 .64 (m, IH), 1.70 to 1.7.9 (m, IH), 1.89 to 1.95 (m, IH), 1.98 to 2.65 (m, IH), 2.1 1 (s, H ), 2.22 (dd, 1H, J= 17.6 Hz and 8.0 Hz), 3.21 (dt, IH, J= 8.2 Hz and 2.0 Hz), 3.33 (t, IH, .1 = 8.0 Hz), 4.07 (s, 2H), 6.96 (d, I H, J= 5.2 Hz), 7.08 to 7.10 (m, 2H), 7.22 to 7.31 (m, 3H ), 8.39 (d, IH, J= 4.8 Hz), 8.76 (s, I H). ^{, 3}C NMR (CDCh, I 00 MHz) δ 22.9, 34.4, 38.0, 40.7. 57.1 , 65.9, 125.0, 126.7, 128.8, 129.1 , 137.4, 139.4, 147.6, 148.1 , 149.8. HRMS (calculated: 253.1705, found: 253.1695). EXAMPLE 12 l-[3-((2S)-l -Methylpyrrolidiπ-2-yl)-4-fu ranyl ((l,4-dihydropyridyl)]-2,2-dimethylpropan-l-one Freshly distilled furan ( 1.29 mL, 17.8 mmol) was added dropwise to n-BuLi (8.5 mL, 1 7.8 mmol) in 5 mL THF at -20 °C and stirred for 0.5 hours. The resulting lithiate was canulated into a suspension of magnesium bromide etherate (4.6 g, 1 7.8 mmol) in 10 mL THF and stirred at room temperature for 1 hour. The mixture turned brown in color. Next, the Grignard reagent was added slowly to a solution of CuBr«DMS ( 1 .73 g, 8.4 mmol) in 15 mL of THF at -78 °C, and the resulting yellow-orange organocopper reagent was stirred for 30 minutes. Concurrently in a separate flask, pivaloyl chloride (9Λ5 LIL, 8 mmol) was added to nicotine ( 1.28 mL, 8 mmol) in 5 mL of THF at 0 °C, and the mi xture was stirred for 1 hour to form a heterogenous mixture containing the white, solid 1-acyl pyπdinium salt. The mixture was cooled to -78 °C, and the organocopper reagent was added via a jacketed (dry ice) double tipped needle. The resulting mixture was stirred for 12 hours. The reaction mixture was quenched with 2 mL of saturated NH₄C1, and the white solid formed was removed by vacuum filtration. The filtrate was extracted with EtOAc (3 10 mL), and the combined organic extracts were washed with 10% NH OH (aq) until the persistent blue color vanished from the organic phase. The organic layer was washed with saturated aqueous NaHCO₃, dried (K₂CO₃), filtered over Celite, and concentrated in vacuo. The crude yellow oil was purified by radial PLC (silica gel, 1% TEA/EtOAc) to give 1.94 g (77%) of product. [α] „ -33.8 (c 2, EtOH. IR (neat) 739, 843, 1015, 1184, 1266, 1409, 1480, 1598, 1666, 2968, 3052, 3406 cm^"1. Η NMR (CDC1₃ 300 MHz) δ 1.26 (m, I H), 1 .38 (s, 9H), 1.72 to 1.39 (m, 3H), 2.09 (q, IH, J= 9.2 Hz), 2.16 (s, 3H), 2.44 (t. IH, J- 7.6 Hz), 3.02 (t, IH, 9.0 Hz), 4.13 (d, l H, J= 4.0 Hz), 5.04 (q, IH, J= 3.2 Hz), 6.05 (d, 1H, J = 32 Hz), 6.28 (m, IH), 7.25 (d, I H, J = 8.0 Hz), 7.30 (s, IH), 7.39 (s, IH); ¹³C NMR (CDCI₃, 100 MHz) δ 22.8, 27.0, 28.5, 32.9. 36.8, 39.7, 40.8, 56.8, 69.4, 106.2, 107.8, 110.6, 11 1.9, 1 18.2, 120.3, 121.0, 124.3, 141 .4, 145.2, 157.1 174.2. HRMS (calculated: 315.2073, found: 3 15.2086.

EXAMPLE 13 Preparation of l-[4-tert-butoxymethyl-3- (l-methylpyrrolidin-2-yl)-4H-pyridin-l-yl]-2,2-dimethyl-propan-l-one

Potassium tert-butoxide (0.5 g, 4 mmol) was suspended in 16 mL of tert-butylmethyl ether (TBME). After cooling at -78 °C, the well stirred mixture was treated with tert- butyllithium (3 mL, 4 mmol) over 2 min. A bright orange color was observed and stirring at ■ 78 °C was continued for 2 h. A solution of CuBr»SMe₂ (0 4 g, 2 mmol) in isopropyl sulfide (3 mL) and TBME (5 mL) was slowly added. The resulting cuprate solution was stirred at - 78 °C for 40 min. In a separate flask, a solution of nicotine (0.16 L, 1 mmol) in THF (1 mL) was cooled to 0 °C and treated with pivaloyl chloride (0.12 mL, 1 mmol). The mixture was stirred at 0 °C for 1.5 h. It was then cooled to -78 °C and treated with the cuprate solution prepared above. The reaction mixture was stirred for 3 h at -78 °C. After addition of a saturated aqueous solution of NH CI (20 mL), the aqueous layer was extracted with EtOAc (3 X). The combined organic layers were washed with 20% NH Cl/NH₄OH, water and brine and were dried over K CO₃. After evaporation of the solvent under reduced pressure, the cnide material was purified by radial PLC (hexanes) to afford 0.217 g (58%) of \-[A-tert- butoxymethyl-3-(l -methylpyτrolidin-2-yl)-4H-pyridin- l-yl]-2,2-dimethyl-propan-l-one as a yellow oil. IR (thin film, neat, NaCl) 2968, 1661, 1311 cm^'1 ; Η NMR (CDC1₃, 400 MHz) δ 7.21 (s, 1 H), 7.07 (d, I H, J= 8 Hz), 5.24 (dd, 1 H, J- 4.8 and 8 Hz), 3.58 (dd, 1 H, J- 4 and 8 Hz), 3.12 (t, 1 H, J= 8.8 Hz), 3.07 - 3.00 (m, 2 H), 2.57 (t, 1 H, J = 6.8 Hz), 2.28-2.08 (m, 5 H), 1.94-1.70 (m, 4 H), 1.35- 1.12 (m, 19 H); ¹³C NMR (CDCI₃, 100 MHz) δ 173.4, 173.3. 123.7, 122.9, 1 19.9, 1 10.3, 72.3, 72.2, 70.3, 66.0, 56.6, 40.2, 39.2, 39.1, 36.2, 31.0, 28.0, 27.9, 27.3, 27.2, 22.6; HRMS Calcd for C₂₀H₃₄N₂O₂: 335.2699 [M+H]⁺. Found: 335.2715 [M+H]⁺. [α] £-9.6 (c 4.3, CH₂C1₂).

EXAMPLE 14 Preparation of 4-tert-butoxymethyl-3-(l-methy!pyrrolidin-2-yl)-pyridine

S, toluene A solution of l-[4-ter/-butoxymethyl-3-(l-methylpyrrolidin-2-yl)-4H-pyridin- l -yl]- 2,2-dimethyl-propan- l-one (0.194 g, 0.5 mmol), sulfur (0.02 g, 0.5 mmol) and toluene (5 mL) was refluxed for 1 day. After filtration of the mixture through a pad of Celite and evaporation of the solvent under reduced pressure, the crude material was purified by radial PLC (hexanes) to afford 0.091 g (54%) of 4-tert-butoxymethyl-3-( l -methylpyrrolidin-2-yl)- pyridine as a yellow oil. IR (thin film, neat, NaCl) 2970, 2778, 1594, 1362, 1 193, 1088 cm^{" 1} , Η NMR (CDC , 400 MHz) δ 8.72 (s, 1 H), 8.45 (d, I H, J = 6.4 Hz), 7.40 (d, 1 H, J = 6.4 Hz), 4.52 (s, 2 H), 3.32-3.20 (m, 3 H), 2.32-2.22 (m, 2 H), 2.18 (s, 3 H), 1.96-1.66 (m, 4 H), 1.29 (s, 9 H); ^l C NMR (CDC1₃, 100 MHz) δ 148.3, 147.7, 146.2, 135.3, 121.4, 73.4, 65.2, 59.6, 56.5, 40.2, 33.7, 27.20, 22.4; HRMS Calcd for Cι₅H₂₄N₂O: 249.1967 [M+H]⁺. Found: 249.1964 [M+H]⁺. [α] " -108.2 (c 3.4, CH₂C1₂).

EXAMPLE 15 Preparation of l-[4-benzyloxymethyl-3- (l-methylpyrrolidin-2-yI)-4H-pyridin-l-yl]-2,2-dimethyl-propan-l-one

To a stirred solution of (benzyloxymethyl)tributyl stannane (prepared according to reference 1) (0.308 g, 0.75 mmol) in THF (0.75 mL) cooled at -78 °C was added n- butyllithium (0.35 mL, 0.75 mmol). After stirring at -78 °C for 30 min. the Lipshultz reagent (3 L, 0.75 mmol) was introduced dropwise, and the mixture was allowed to stir for 30 min at -78 °C. In a separate flask, a stirred solution of nicotine (0.08 mL, 0.5 mmol) in THF ( 1 L) was cooled at 0 °C and treated with pivaloyl chloride (0.06 mL, 0.5 mmol). This solution was then stirred at 0 °C for 1.5 h. The cuprate solution prepared above was then transferred via a double tipped needle surrounded by a layer of dry ice to the pyridinium salt of nicotine previously cooled to -78 °C. After addition of a saturated aqueous solution of NH₄CI (10 mL), the aqueous layer was extracted with EtOAc (3 x). The combined organic layers were washed with 20% NH₄Cl/NH OH, water and brine, and were dried over K C0₃. After evaporation of the solvent under reduced pressure, the crude material was purified by radial PLC (hexanes) to a! ford 0.107 g (70%) of l-[4-benzyloxymethyl-3-( I - methylpyrrolidin-2-yl)-4H-pyridm- l -yl]-2,2-dimethyl-propan-l -one as a yellow oil. IR (thin film, neat, NaCl) 2928, 1772, 1 724, 1656, 1599, 1454, 1364, 1267, 1 1 53, 1 100 cm^{' 1} ; Η NMR (CDC1₃, 400 MHz) δ 7.01 6.94 (m, 5 H), 6.80 (d, 1 H, J = 8 Hz), 4.93 (dd, 1 H, J = 4.8 Hz and 8 Hz), 4.18 (d, 2 H, J -^" 6.8 Hz), 3.37 (dd, 1 H, J - 4 Hz and 8.4 Hz), 3.05 (t. I H, J = 8 Hz), 2.87 - 2.83 (m, 1 H), 2.74 (t, 1 H, J= 7.6 Hz), 2.25 (t, 1 H, J= 7.6 Hz), 1.85 (s, 3 H), 1 .81 - 1.77 (m, 1 H), 1.58 - 1.37 ( , 4 H), 1.01 (s, 9 H); ¹³C NMR (CDC1₃, 100 MHz) δ 173.65, 138.51, 128.09, 127.28, 127.22, 124.40, 123.45, 1 19.32, 109.80, 74.32, 72.78, 70.55, 56.69, 40.32, 39.31 , 35.62, 30.74, 28.06, 22.74; HRMS Calcd for C₂₃H₃₂N₂O₂: 369.2542 [M+H]⁺. Found: 369.2543 [M+H]⁺. [ ]²⁸ _D +26.6 (c 5.6, CH₂C1₂). Reference 1 : Kaufman, T. S. Svnlett, 1997, 1377.

EXAMPLE 16 Preparation of 4-benzyloxymethyl-3-(l -methylpyrrolidin-2-yl)-pyridine

S, toluene A solution of l-[4-benzyloxymethyl-3-(l-methylpyrrolidin-2-yl)-4H-pyridin-l-yl]- 2,2-dimethyl-propan-l-one (0.176 g, 0.48 mmol), sulfur (0.015 g, 0.48 mmol) and toluene (5 mL) was refluxed for 3 days. After filtration of the mixture through a pad of Celite and evaporation of the solvent under reduced pressure, the crude material was purified by radial PLC (hexanes) to afford 0.08 g (60%) of 4-benzyloxymethyl-3-( l-methylpyrrolidin-2-yl)- pyndine as a yellow oil. IR (thin film, neat, NaCl) 3436, 1637, 1090 cm^"1; 1H NMR (CDC1₃, 300 MHz) δ 8.74 (s, 1 H), 8.47 (d, 1 H, J = 4.8 Hz), 7.40 - 7.27 (m, 6 H), 4.62 (d, 2 H, J = 13.2 Hz), 3.34 - 3.18 (m, 2 H), 2.28 - 2.18 (m, 2 H), 2.15 (s, 3 H), 2.11 - 1.09 (m, 5 H); ^{l 3}C NMR (CDCI₃, 75 MHz) δ 149.31 , 148.37, 145.16, 137.86, 128.67, 128.06, 127.98, 122.14, 72.92, 68.19, 65.88, 57.07, 40.75, 34.28, 27.83, 22.91 ; HRMS Calcd for C,,sH₂₂N₂O' 283.1810 [M+H]⁺. Found: 283.1800 [M+H]⁺. [α] % -75.9 (c 2.5, CH₂C1₂). The foregoing is illustrative of the present invention, and is not to be construed as limiting thereof. The invention is defined by the following claims, with equivalents of the claims to be included therein.

Claims

THAT WHICH IS CLAIMED IS: 1. A method of making a compound of Formula I:

wherein: R⁴ is alkyl, alkenyl, alkynyl, aryl or SiR²⁰R^{2 ,}R²², wherein R²⁰, R²¹ and R²² are each independently selected from the group consisting of alkyl, alkenyl, alkynyl and aryl; R^] is alkyl, aryl, alkenyl, alkynyl, alkoxy, -NR"₂ or -SR", where R" is alkyl, aryl, alkenyl, alkynyl, or alkoxy; R^", R⁵, and R are each independently selected from the group consisting of H^', alkyl, aryl. alkenyl, alkynyl, alkoxy, and halo; R⁷ is selected from the group consisting of consisting of H and alkyl; A is a 1, 2 or 3 atom bridging species which forms part of a saturated or mo no unsaturated 5-, 6- or 7-membered ring including N⁷, C , C⁹ and B; B is selected from -0-, -S-, -NR¹⁰-, wherein R¹⁰ is selected from hydrogen, alkyl, aryl, substituted aryl, alkylaryl, substituted alkylaryl, arylalkyl, substituted arylalkyl; -C¹⁰HR^10a-, wherein R^10a is selected from hydrogen, alkyl, hydroxyalkyl, aryl, aryloxyalkyl, fiuoro, tn tluoromethyl, cyano, cyanomethyl, -OR', -NR'2, or — SR', wherein each R is independently hydrogen, alkyl, alkenyl, alkynyl or aryl; or B is =C¹⁰R^10a or =N-; and R and R ^a are each independently selected from hydrogen, alkyl, hydroxyalkyl, aryl, aryloxyalkyl, fiuoro, trifluoromethyl, cyano, cyanomethyl. -OR', -NR'₂, or -SR', wherein each R' is as defined above; comprising reacting an organometalhc nucleophile R⁴Met, where R⁴ is as given above and Met is a metal, with a compound of the formula:

wherein A, B, R², R⁵, R⁶, R⁷, R⁹, and R^9a are as given above, and a compound of the formula R'COX¹, wherein R¹ is as given above and X¹ is halo, to produce a compound of Formula I.

2. The method of claim 1 , wherein R⁴ is alkyl, alkenyl, alkynyl, or aryl.

3. The method of claim 1 , wherein R⁴ is SiR-V'R²², and wherein R , R²¹ and R²² are each independently selected from the group consisting of alkyl alkenyl, alkynyl and aryl.

4. The method of claim I, wherein R¹ is alkyl.

5. The method of claim 1 , wherein Met is selected from the group consisting of magnesium, manganese, sodium, lithium, copper, cerium, zinc, cadmium, aluminum and titanium.

6. A compound of Formula I:

wherein: R⁴ is alkyl, alkenyl, alkynyl, aryl or SiR ⁰R^2l " wherein R²⁰, R²¹ and R²² are each independently selected from the group consisting of alkyl. alkenyl, alkynyl and aryl; R¹ is alkyl, aryl, alkenyl, alkynyl, alkoxy, -NR" or -SR", where R" is alkyl, aryl, alkenyl, alkynyl, or alkoxy; R², R⁵, and R^fl are each independently selected from the group consisting of H, alkyl, aryl, alkenyl, alkynyl, alkoxy, and halo; R⁷ is selected from the group consisting of consisting of H and alkyl; A is a 1, 2 or 3 atom bridging species which forms part of a saturated or monounsaturated 5-, 6- or 7-membered ring including N⁷, C⁸, C⁹ and B; B is selected from -0-, -S-, -NR¹⁰-, wherein R¹⁰ is selected from hydrogen, alkyl, aryl, substituted aryl, alkylaryl, substituted alkylaryl, arylalkyl, substituted arylalkyl; -C^l0HR^10a-, wherein R^i0a is selected from hydrogen, alkyl, hydroxyalkyl, aryl, aryloxyalkyl, fluoro, trifluoromethyl, cyano, cyanomethyl, -OR', -NR'?, or -SR', wherein each R' is independently hydrogen, alkyl, alkenyl, alkynyl or aryl; or B is =C^loR^{I Oa} or =N-; and R⁹ and R^9a are each independently selected from hydrogen, alkyl, hydroxyalkyl, aryl, aryloxyalkyl, fluoro, tπfluoromethyl, cyano, cyanomethyl, -OR', -NR'₂₎ or -SR', wherein each R' is as defined above.

7. The compound of claim 6, wherein R⁴ is alkyl, alkenyl, alkynyl, or aryl.

8. The compound of claim 6, wherein R⁴ is SiR^2ϋR²¹ R²², and wherein R²⁰, R²¹ and R²² are each independently selected from the group consisting of alkyl, alkenyl, alkynyl and aryl.

9. The compound of claim 6, wherein R¹ is alkyl.

10. The compound of claim 6, wherein said compound is enantiomerically pure.

1 1. A method of making a compound of Formula II:

wherein R⁴ is alkyl, alkenyl, alkynyl, aryl or SiR²⁰R^2lR²², wherein R²⁰, R²¹ and R²² are each independently selected from the group consisting of alkyl, alkenyl, alkynyl and aryl; R², R⁵, and R⁽¹ are each independently selected from the group consisting of H, alkyl, aryl, alkenyl, alkynyl, alkoxy, and halo; R is selected from the group consisting of consisting of H and alkyl; A is a I , 2 or 3 atom bridging species which forms part of a saturated or monounsaturated 5-, 6- or 7-membered ring including N⁷, C⁸, C⁹ and B; B is selected from -O-, -S-, -NR¹⁰-, wherein R¹ is selected from hydrogen, alkyl, aryl, substituted aryl, alkylaryl, substituted alkylaryl, arylalkyl, substituted arylalkyl; -C^{, 0}HR^IOa-, wherein R^10a is selected from hydrogen, alkyl, hydroxyalkyl, aryl, aryloxyalkyl, fluoro, trifluoromethyl, cyano, cyanomethyl, —OR', -NR'₂, or -SR'. wherein each R' is independently hydrogen, alkyl, alkenyl, alkynyl or aryl; or B is =C^l0R^{l 0a} or =N-; and R⁹ and R^9a are each independently selected from hydrogen, alkyl, hydroxyalkyl, aryl, aryloxyalkyl, fluoro, tπ fluoromethyl, cyano, cyanomethyl, -OR', -NR'₂, or -SR', wherein each R' is as defined above, comprising oxidizing a compound of Formula I:

wherein A, B, R², R⁴. R³, R⁶, R⁷, R⁹, and R^9a are as given above, and R¹ is alkyl, aryl, alkenyl, alkynyl, alkoxy, -NR"₂ or -SR", where R" is alkyl, aryl, alkenyl, alkynyl. or alkoxy, to produce a compound of Formula II.

12. The method of claim 1 1, wherem said solvent is toluene.

13. The method of claim 1 1, wherein said oxidi/ing step is earned out w ith an oxidizing agent selected from the group consisting of air, sulfur, nitric acid, KJVI ΠO , eerie ammonium nitrate, chloranil and 2,3-dichloro-5, 6-dicyano- l , 4-benzoquinone.

14. The method of claim 1 1 , wherein R is alkyl, alkenyl, alkynyl, or aryl.

15. The method of claim 11, wherein R⁴ is SιR²⁰R²¹R²², and wherem R²⁰, R²¹ and R²² are each independently selected from the group consisting of alkyl alkenyl, alkynyl and aryl.

16. An enantiomerically pure C4-substituted nicotine analog produced by the process of claim 11.

17. An enaniiomerically pure compound of Formula II:

wherein: R⁴ is alkyl, alkenyl, alkynyl, aryl or SiR²⁰R^{2 l}R²², wherein R²⁰, R²¹ and R²² are each independently selected from the group consisting of alkyl alkenyl, alkynyl and aryl, R , R³, and R° are each independently selected from the group consisting of H, alkyl, aryl, alkenyl, alkynyl, alkoxy, and halo; subject to the proviso that R⁴ is different from at least one of R², R³ and R⁶; R⁷ is selected from the group consisting of consisting of H and alkyl; A is a 1 , 2 or 3 atom bridging species which forms part of a saturated or monounsaturated 5-. 6- or 7-membered nng including N , C , C and B; B is selected from -O-, -S-, -NR¹⁰-, wherein R¹⁰ is selected from hydrogen, alkyl, aryl, substituted aryl, alkylaryl, substituted alkylaryl, arylalkyl, substituted arylalkyl, -C^HR¹⁰¹¹-, wherein R^10a is selected from hydrogen, alkyl, hydroxyalkyl, aryl, aryloxyalkyl, fluoro, trifluoromethyl, cyano, cyanomethyl, -OR', -NR'₂, or — SR', wherein each R' is independently hydrogen, alkyl, alkenyl, alkynyl or aryl; or B is =C¹⁰R^10a or =N-; and R⁹ and R'^)a are each independently selected from hydrogen, alkyl, hydroxyalkyl, aryl, aryloxyalkyl, fiuoro. trifluoromethyl, cyano, cyanomethyl. -OR', -NR'₂, or -SR'. wherein each R' is as defined e

18. The enantiomerically pure compound of claim 17, subject to the proviso that R⁴ is different from R², R⁵ and R⁽\

19. An enantiomerically pure compound of Formula II:

wherein: R⁴ is SiR²⁰R²¹R²², wherein R²⁰, R²¹ and R²² are each independently selected from the group consisting of alkyl, alkenyl, alkynyl and aryl; R², R⁵, and R⁶ are each independently selected from the group consisting of H, alkyl, aryl, alkenyl, alkynyl, alkoxy, and halo; R⁷ is selected from the group consisting of consisting of H and alkyl; A is a 1 , 2 or 3 atom bridging species which forms part of a saturated or monounsaturated 5-, 6- or 7-membered ring including N , C⁸, C⁹ and B; B is selected from -O-, -S-, -NR¹ -, wherein R¹⁰ is selected from hydrogen, alkyl, aryl, substituted aryl, alkylaryl, substituted alkylaryl, arylalkyl, substituted arylalkyl; -C^{l 0}HR^10a-, wherein R^10a is selected from hydrogen, alkyl, hydroxyalkyl, aryl, aryloxyalkyl, tluoro, trifluoromethyl, cyano, cyanomethyl, —OR', -NR'2, or -SR', wherein each R is independently hydrogen, alkyl, alkenyl, alkynyl on aryl; or B is =C¹⁰R^{I a} or =N-; and R⁹ and R^l>u are each independently selected from hydrogen, alkyl, hydroxyalkyl. aryl, aryloxyalkyl, fluoro, trifluoromethyl, cyano, cyanomethyl, -OR', -NR'₂, or -SR', wherein each R' is as defined above.

20. The compound of claim 19, wherein R\ R^"\ and R are each independently selected from the group consisting of H, alkyl, aryl, alkenyl, and alkynyl.

21. A method of making a compound of Formula III:

wherein: R², R⁵, and R⁶ are each independently selected from the group consisting of H, alkyl, aryl, alkenyl, alkynyl, alkoxy, and halo; R⁷ is selected from the group consisting of consisting of H and alkyl; A is a 1, 2 or 3 atom bridging species which forms part of a saturated or monounsaturated 5-, 6- or 7-membered ring including N⁷, C⁸, C⁹ and B; B is selected from -O-, -S-, -NR¹⁰-, wherein R¹⁰ is selected from hydrogen, alkyl, aryl, substituted aryl, alkylaryl, substituted alkylaryl, arylalkyl, substituted arylalkyl; -C^l0HR"^la-, wherein R^{1 a} is selected from hydrogen, alkyl, hydroxyalkyl, aryl, aryloxyalkyl, fluoro, trifluoromethyl, cyano, cyanomethyl, —OR', -NR'₂, or -SR', wherein each R' is independently hydrogen, alkyl, alkenyl, alkynyl or aryl; or B is =C^ιnR^10a or =N-; and R⁹ and R^9a are each independently selected from hydrogen, alkyl, hydroxyalkyl, aryl, aryloxyalkyl, fluoro, trifluoromethyl, cyano, cyanomethyl, -OR', -NR'₂, or -SR', wherein each R' is as defined above; comprising oxidizing a compound of Formula II:

wherein A, B, R. R², R⁵, R^h, R⁷, R⁹, and R^9a are as given above and R is SiR²⁰R^{2 l} R² , wherein R²⁰, R²¹ and R ^~ are each independently selected from the group consisting of alkyl alkenyl, alkynyl and aryl. in a polar protic solvent to produce a compound of Formula III.

22. The method of claim 21, wherein said solvent is selected from the gonip consisting of methanol, ethanol, propanol, and butanol

23. The method of claim 21, wherein said oxidizing step is earned out with a peroxide in the presence of fluonde

24. An enantiomencally pure compound of Formula III:

wherem: R², R⁵, and R⁶ are each independently selected from the group consisting of H, alkyl, aryl, alkenyl, alkynyl, alkoxy, and halo; R⁷ is selected from the group consisting of consisting of H and alkyl; A is a 1, 2 or 3 atom bndging species which forms part of a saturated or monounsaturated 5-, 6- or 7-membered nng including N⁷, C^x, C and B; B is selected from -0-, -S-, -NR¹⁰-, wherein R¹⁰ is selected from hydrogen, alkyl, aryl, substituted aryl, alkylaryl, substituted alkylaryl, arylalkyl, substituted arylalkyl; -C¹⁰HR^10a-, wherein R^10a is selected from hydrogen, alkyl, hydroxyalkyl, aryl, aryloxyalkyl, fluoro, tnfluoromethyl, cyano, cyanomethyl, —OR', -NR'₂, or — SR', wherein each R' is independently hydrogen, alkyl, alkenyl. alkynyl or aryl; or B is =C^l0R^10d or =N-, and R⁹ and R^9a are each independently selected from hydrogen, alkyl, hydroxyalkyl, aryl, aryloxyalkyl, fluoro, tπfluoromethyl, cyano, cyanomethyl, -OR', -NR'₂, or -SR', wherein each R' is as defined above